Abdominal obesity in normal weight versus overweight and obese hemodialysis patients: Associations with nutrition, inflammation, muscle strength, and quality of life.

Objective: The biological basis of abdominal obesity leading to more severe outcomes in patients with normal body mass index (BMI) on maintenance hemodialysis (MHD) is unclear. The aim of this study was to compare the properties of abdominal obesity in different BMI categories of patients on MHD.

Methods: We performed a cross-sectional study of 188 MHD patients (52.7% women; mean age, 69.4 ± 11.5 y) with abdominal obesity in different BMI groups using criteria from the World Health Organization. Appetite and dietary intake, body composition, handgrip strength, malnutrition inflammation score (MIS), inflammatory biomarkers, adipokines, and health-related quality-of-life (QoL) questionnaires were studied.

Results: According to multivariable analyses, abdominally obese patients with normal BMIs consumed less protein per day (P = 0.04); had lower measurements of surrogates of lean (P < 0.001) and fat mass (P < 0.001); and had higher total cholesterol, tumor necrosis factor-α (P < 0.05), and ratios of adiponectin to leptin (P = 0.003) than overweight and obese patients with abdominal obesity. Multivariable analyses showed no differences in handgrip strength among the study groups.The abdominally obese study participants with normal weight had significantly lower scores in role physical (P = 0.003) and pain (P = 0.04) scales after multivariable adjustments.

Conclusions: Normal-weight MHD patients with abdominal obesity exhibited a more proatherogenic profile in terms of inflammatory markers and adipokine expression, lower body composition reserves, and lower physical ability than patients with abdominal obesity with overweight and obesity. This at least partially explains the abdominal obesity paradox in the MHD population in which worse clinical outcomes are seen in abdominally obese patients with normal BMIs, as opposed to overweight and obese patients who are also abdominally obese.